I built the 50 W amp for 40m. In my testing I found that the amplified signal goes from 80 V P-P after T3 (just before LPF) and drops to 50V P-P after LPF (measured just after c14 before c15).?
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I'm running 12 V and I set the bias at R5 fully counterclockwise (note setting bias as per manual does not change the V drop over LPF). Drive is about 5w coming from QCX+.?
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I triple checked L4, L5 and L6 (all the windings are correct in # and continuity) as well as C14, 18, 11, and 12 (correct values).?
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The signal loses about 30Vp-p amplitude, though it's much cleaner after LPF.?
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I reviewed the N5NY troubleshooting video, and everything checks out. It's just that I'm losing signal at LPF.
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What might likely culprit be? Thinking it might be one of the capacitors in LPF. I'm not sure how to test them without removing from circuit.?
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Thanks for any feedback!
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Charlie
N8DD
